JPH04500626A - osmotic absorbent - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] osmotic absorbent Background of the invention Most natural and synthetic fibers have limited liquid storage capacity; If a liquid is stored in the normal way, the fibers will react to this when subjected to some stress. If such substances are unable to release liquid and require liquid absorption For example, absorbent fibers have found a wide range of uses in disposable absorbent Used in body products. These products include diapers, feminine hygiene products, and hospital disposables. products (hospital disposable), surgical bandages, and industrial There are industrial-ial wipes, and these disposable absorbent The largest market for body products is baby diapers. Currently, disposable diapers are made of absorbent materials. Wood fluff or superabsor Bent) using any of the following combinations with polymer gel powder fluff.

Usodofuraf has individual fibers that are usually long, thin ribbons of about 20 to about 10 0 individual consisting of a blend of wood fibers with a cross-sectional size in the range of 0 microns The fiber density is approximately 0. It is within the range of 9 to about 1.1 g/cj. But in diapers Wood fluff when used as an absorbent mat has a preferable value of 0.0Rg/cj. It has a high key density. This density difference creates a large void volume between individual fibers. , where the absorbed liquid is stored. However, due to capillary action, this liquid Since it is maintained on the outer surface of the fibers, this liquid is easily released by stress. Ugh Under a stress of 1.0OOG, the capacitance of Dofurafu ranges from about xog/g to about 1 g/g. It has been reported that there is a decrease in Therefore, wood fluff was used as an absorbent material. Diapers reduce fluid content, creating a wide variety of problems.

Osmotic pressure absorber (os+wotic absorbent) stated in the claims of the present invention ) is an expanding membrane system that seals water inside the membrane shell (we■-brans　5hell). be. This volume expansion is the mechanism by which a larger absorption capacity can be obtained, so the present invention One important aspect is that compared to static, non-expandable structures such as wood fluff, The osmotic volume expansion observed by these osmotic absorbers is 2100 wt. % or more of absorption space.

Zhao absorbent polymers (AGM’s) used in diaper applications have a small proportion of crosslinking. is a high molecular weight ionic polymer containing Control of this crosslinking density in AGM’s The control produces particles that are insoluble in water and a swelling capacity for volume expansion. U.S. Patent No. 4, No. 703.067 is a solid water-absorbing crosslinked polyacrylate produced by polymerization without external heating. This paper describes a method for producing the resin. U.S. Patent No. 4,677.174 covers various describes a water-absorbing cross-linked acrylate resin copolymer produced by aqueous polymerization of I'm looking forward to it. In either case, membrane structures such as these osmotic absorbers are not included. The osmotic pressure absorber of the present invention has the advantage of AGM's in that it is a volume expansion system. Including advantageous aspects.

AGM’s condyle is supported by a Woodfluff matrix within the diaper core. Typically dispersed as granules. The thin ribbon-like nature of wood fibers enters the core of the diaper. AGM serves as a vehicle for irreversible storage, helping to capture and distribute liquids. Therefore, another advantage of the osmotic absorber of the present invention is improved irreversible liquid It is storage.

These osmotic absorbers contain a membrane component, which allows liquid to flow into the shell in a diffusion-controlled process. The body absorbs the molecules, which pass through the osmotic gradient pathway (oawotic gradient path). spread across the thwa. Since external stresses and forces are not required and are not introduced , the flow rate is allegorically lower than that achieved in the case of normal reverse osmosis (RO) membrane action. Yes, in some respects, i.e. when the applied pressure drop is small or not present at all. The osmotic absorber of the present invention involves a dialysis process. The main effect is one when the key difference is the chemical potential of their melts. 0 example defined as a process that is the transfer of 0 molecules from one liquid to another For example, a normal dialysis membrane used for hemodialysis has a molecular weight of more than 1000 atomic units. It has a molecular weight cutoff.

Osmotic pressure is a number-dependent phenomenon; therefore, high flow rates from osmotic pressure differences are requires a large number of molecules. Therefore, the promoter components of these osmotic absorbers has a low value of less than 500 atomic mass units for both weight and volume effects. It is a molecular weight species. In direct contrast to dialysis, these osmotic absorbers can be used for RO or ultrafiltration. Use membrane components that have properties.

absorbs several times its weight in liquid, and the amount of liquid absorbed increases, as detailed further below. The osmotic absorber is manufactured in an amount greater than the amount of liquid absorbed by said prior art absorber. was discovered this time.

Power station-9-Overview As previously mentioned, disposable absorbent materials or products find a variety of uses in the commercial field. I think it will be released. Until now, these absorbent products were typically made from bovine fluff or poultry. It consists of a composition such as a combination of Remargel and Wood Fluff. of these products Liquid retentve property is the target The term “liquid retention” refers to both the amount of liquid and the reversibility of the retention. up to more than 2100% of the total absorbent weight, as further detailed below. Osmotic absorbers can now be manufactured that have the ability to absorb and retain liquids in amounts of Found twice.

It is therefore an object of the present invention to provide an absorbent body.

Another object of the invention is to irreversibly absorb liquid in an amount significantly exceeding the weight of the absorbent body. The object of the present invention is to provide an osmotic absorber having the ability to

In one form, embodiments of the invention provide a high osmolality product. Encapsulated polymer half containing romator inside It is an osmotic pressure absorber consisting of a permeable membrane shell.

A particular embodiment of the invention is a polymeric semi-permeable material made of encapsulated cellulose acetate. comprising a membrane shell, the membrane shell having a thickness in the range of about 5 to about 30 microns; , which contains a high osmolality promoter consisting of sodium chloride. It's in the absorber.

Highlights q Details Plate As mentioned above, the present invention relates to osmotic absorbers. These products have high male inside It consists of an encapsulated polymer semi-i3 membrane shell containing a morality promoter. these Absorbers find a wide variety of uses. For example, substances with high absorption values Used in disposable absorbent products such as diapers. Diapers usually have a concentration of about 1% It is designed to absorb urine, which is a weak salt solution with a Diaper design currently uses wood fluff mixed with a Zhao absorbent polymer. Most currently used The boppier polymer is a derivative of cross-linked polyacrylic acid and absorbent gelling agent ( AGM). Regarding the stock solution, certain other design constraints (co -nstraint), the liquid absorption by AGM is approximately 3 Limited to 0% by weight. The mechanism of AGM swelling is mainly due to osmotic pressure. , this mechanism is limited by the weight percent of the osmotic promoter contained within the construct. It will be done. In contrast, the osmotic absorbers of the present invention can be osmotic at arbitrarily elevated concentrations. Use pressure promoters or high osmolality promoters. More details below Various types of high osmolality promoters can be used, as described above. This is a limitation of the combined use of ionic species as AGM and osmotic promoters. In contrast to degree. Therefore, the high osmolarity of the promoter of the present invention is due to this Considering the fact that the osmotic absorber of the present invention is not limited to It has been discovered that it has an absorption capacity that greatly exceeds the absorption capacity.

The above considerations focused on the use of osmotic pressure absorbers in diaper applications. However, the specific polymeric membrane shell and osmolarity promoter used by the absorbent It is within the scope of the present invention that it may also be utilized in other ways according to For example, using the absorbent body of the invention, the presence of undesirable liquids, such as water, can be prevented from carbonizing. Remove undesirable liquids from hydrogen fuels if they adversely affect the use of said fuels. It can also be removed.

As mentioned above, the osmotic absorption of the present invention has a built-in high osmolality promoter. It consists of an encapsulated polymeric semipermeable membrane shell. Used as a shell component of VjL receptor Polymer semipermeable membrane highly rejects osmotic promoters and has good water permeability It is a polymer membrane with a Membranes with these properties have good water absorption into the membrane shell. or allow the influx of liquid and form a high osmotic pressure difference. Some of the polymer membranes Typical examples include cellulose acetate, including diacetate and triacetate. , such as methylcellulose, ethylcellulose, propylcellulose, nitrose Cellulose acetate derivatives such as lulose, sulfonated polysulfones, e.g. For example, polystyrene sulfonate and polybenzyltrimethylammonium chloride complexes with, such as nylon 4, nylon 6, nylon 7, nylon 8, nylon Made from long chain polymer amides including various nylons such as Nylon 9, Nylon 66, etc. manufactured products, such as polyethers such as polyethylene glycol and isocyanate by reacting with incyanate such as luene diisocyanate isocyanate-capped pol after which the polyether is coated with, for example, polyvinylpyrroli such as those produced by mixing heterocyclic nitrogen-containing compounds such as gin Interpenetrating polymer network membranes, e.g. For example, aromatic polyamines can be added to aromatic polycarboxylic acids such as trimesoyl chloride. There are membranes produced by reacting with loride to form interfacially polymerized polymers. Ru. Although the polymer itself can be used as the shell itself, e.g. on porous support backing materials like polysulfone, polycarbonate etc. Supporting is also contemplated within the scope of the invention.

High osmolality, which forms the second component of the absorber and is encapsulated within a polymer membrane shell. The promoter has a good rejection rate by the membrane. These high osmolality promoters are preferably low molecular weight water-soluble components. Some typical examples of salts include, for example, lithium chloride, sodium chloride, Potassium, rubidium chloride, calcium chloride, barium chloride, magnesium chloride , lithium oxalide, sodium oxalide, potassium oxalide, rubidium oxalide such as calcium oxalide, barium oxalide, magnesium oxalide, etc. halide salts of groups A and mA of the periodic table; e.g. glucose, sucrose, Sugars such as luctose; polyesters such as glycerol, ethylene glycol, etc. Polyhydric compound; for example, water Ammonium compounds such as ammonium oxide, ammonium chloride etc; lactic acid; charcoal Potassium oxyhydrogen, sodium hydrogen carbonate, sodium hydrogen carbonate, etc. As a membrane layer The above list of polymers and osmotic promoters can be used to form osmotic absorbers. These are merely representative of the types of compounds that can be used, and the present invention is not necessarily limited thereto. It should be understood that this is not the case.

Osmotic absorption consisting of an encapsulated polymeric semipermeable membrane shell containing an osmotic promoter inside. The body has a polymer:promoter weight ratio in the range of about 2=1 to about 1=10. The amount of osmotic promoter used is determined by the amount of polymer - depends on the weight of the The weight of the latter depends in this case on the thickness of the polymer semipermeable membrane shell. However, in a preferred embodiment of the invention, the thickness is within the range of about 5 to about 30 microns. It is.

The shape of the osmotic absorber can vary widely. Some shapes of osmotic absorbers Typical examples include sheets, spheres, hollow fibers, etc. These absorbers are known in the art. For example, if the osmotic pressure absorber is to be made into a sheet shape, the osmotic pressure Inserting one layer of promoter between the top and bottom layers of the membrane, then laminating said layers. , forming an enveloped shell containing an osmotic promoter encapsulated inside. Similarly, The tomopromoter, especially if there is a solid form, can be coated with a preferred polymer and its and subsequent processing to form the preferred film. Similarly, the osmotic pressure absorber can be made into hollow fibers. If necessary, the fibers are coated with a polymeric semipermeable membrane, again by methods known in the art. after which the osmotic promoter is encapsulated within the length of the fiber, and then Seal each end of the IIhm length to prevent leakage.

Disaster - Disaster - 1 In this example, a polymer with a size of 3X3C1 and a thickness of 20 microns A sheet of cellulose acetate was placed on a flat surface. glucose and soufflo Varying amounts of osmotic promoters, including The polymer cellulose acetate of the sheet is combined with the first sheet and the osmotic pressure promoter. placed at the top. Seal the edges by softening the polymer and seal each packet ( Weigh the package t). O encapsulated in polymer cellulose acetate The osmotic absorber packet consisting of smolarity promoter is placed in water for 30 minutes. The time was set within 60 minutes. After this, remove the packet from the water and use the absorbent The soak weight was obtained by pressing dry with a paper towel. The results of this test are below Packets A, B, C, and D in Table 0 shown in Table 1 contain species as osmotic promoters. Buckets containing varying amounts of glucose) E is sucrose as an osmotic promoter. Contained.

11-Table 0 0.043 LiC1; 0.074 20m 7.0cm O0%30 2 128% 60 3170% 90 3979% P　O,056LiC1;0.110　16111　11.5CIl　O0%3 0 2404% 60 3212% Q　O,070LiC1;0.112　22m　10.0c11　0　0%30 　2313% 60 3416% 90 4180% Husband - family member - ■ Various amounts of sodium chloride were added to the above example in the same manner as described in Example ■ above. A polymer consisting of cellulose acetate with the same surface area and thickness as mentioned. Osmotic absorber packets were manufactured by encapsulating within a semi-13WA shell. .

Packets named F, G, H1■ and J were placed in water for 90 to 1060 minutes. Soaked for a period within the range. At the end of the above period, remove the packet and insert the absorber. It was patted dry with a paper towel and weighed. These test results are shown below. Shown in Table 2.

箪-λ-table FO, 034NaCl; 0.067 0.101 900.596 490% 1456%G O, 050NaCl; 0.036 0.0B6 3501.0 42 1112% 1912% HO, 040NaCl; 0.046 0.0B6 2400.875 917% 1973%1 0.251 NaCl; 0.1 36 0.387 3006.221 1507% 2324% J O, 187 NaC1; 0.251 0.438 10609.616 2100% 490 8% implementation-flu Sodium chloride, sucrose and glucose as high osmolality promoters As described in the example above, using cellulose acetate as the polymeric semipermeable membrane. Using the same method as above, we manufactured 4 packets and sealed them. Later, 3 of the 4 packets were soaked in water, and the 4th packet was soaked with 1% salt by weight. immersed in a solution containing sodium chloride. Soak the packet for up to 48 hours Ta. During this 48 hour period, the packets are collected and dried at various intervals. and weighed. The results of these tests are shown in Tables 3 and 4 below.

In the test, packets L and M were immersed in water, and packet N was immersed in sodium chloride. immersed in um solution.

11-Table Polymer weight (6) 0.18? 0.056 0.212 0.158 promo One body NaCl Scroll Glucose NaCl promoter weight (8 ) 0.251 0.134 0.436 0.156th-Sat-l I made it a bomber KL　M　N Polymer weight Cg) 0.187 0.056 0.212 0.158 Promo One body NaCl Scroll Glucose NaCl promoter weight (8 ) 0.251 0.134 0.436 0.156 - 1 minute 1' o　o　o　o　.

1.060 4908 − − − From the table above, it is clear that each packet contains approximately 2,000% or more of the promoter weight. The water absorption rate based on the weight of the polymer is 2.1 of that of sodium chloride solution. It ranged from 62% to over 4,600% water by weight. @Yield comparison , an osmotic promoter with a large osmolarity has a small osmolarity. It was discovered that the osmotic promoter allows for greater flux than the osmotic promoter. Show. In addition, the amount of water absorbed in the test using IJ'J molten liquid (1% chloride) was The presence of sodium chloride in the solution suppresses the difference in salt gradient between the inside of the packet and the absorption solution. As long as pressure is applied, low water absorption rate is produced.

Implementation - Implementation - N Hollow fibers with a relatively large circumference were made from cellulose acetate. fiber length , seal one end, and add various amounts of lithium chloride to the high osmolality promoter. The remaining ends are sealed and the osmotic suction formed is placed inside the hollow fiber as a The objects were named O, P, and Q. These long, thin packets are placed in water for 90 minutes. Soaked until dry, removed periodically, patted dry, and weighed. these The test results are listed in Table 5 below.

0 0.043 LiCl; 0.074 20m 7.0cm O0%30 2 128% 60 3170% 90 3979% P　O,056LiCl0.110　16111　11.5C1100%30 2404% 60 3212% Q 0.070 LiC1; 0.112 22+m 10.0C1100%30 　2313% 60 3416% 90 4180% Quiet summit inspection report 1+n++au. , , , , , , , -, , PCT/l;S 8910407 4 International search report IJs B904074 S^　31444

Claims (11)

[Claims] 1. An encapsulated polymer semipermeable membrane shell containing a high osmolality promoter inside. An osmotic pressure absorber consisting of 2. 2. The polymer semipermeable membrane shell has reverse osmosis or ultrafiltration properties. osmotic pressure absorber. 3. 2. The osmolarity promoter of claim 1, wherein the osmolarity promoter has a molecular weight of less than 500. Osmotic pressure absorber. 4. The weight ratio of polymer membrane to promoter is in the range of about 2:1 to about 1:10. The osmotic pressure absorber according to claim 1. 5. The osmolarity promoter is a metal of Group IA or Group II of the periodic table. The osmotic absorber according to claim 3, wherein the osmotic pressure absorber is selected from the salts of. 6. The osmotic absorber according to claim 5, wherein the salt is sodium chloride. 7. The osmotic pressure absorber according to claim 5, wherein the salt is lithium chloride. 8. 4. The osmotic agent according to claim 3, wherein said high osmolarity promoter is glucose. Pressure absorber. 9. 4. The infiltration system of claim 3, wherein said high osmolarity promoter is sucrose. Pressure absorber. 10. The osmotic pressure according to claim 1, wherein the polymer semipermeable membrane is cellulose acetate. Absorber. 11. 5. The thickness of said polymeric semipermeable membrane is within the range of about 5 to about 30 microns. The osmotic pressure absorber according to 1.